IRIS Movie of the Day
At least once a week a movie of the Sun taken by NASA's Interface Region Imaging Spectrograph (IRIS) is posted by one of the scientists operating the instrument.
Limb Flare in AR12555 Colorized
Credit: IRIS, LMSAL/NASA, Roy Smart
In this video, we have used IRIS's spectrograph to colorize the grayscale images captured by the 1400 Angstrom imaging channel during a B5.5 flare. Since the spectrograph has a very small field of view, we can only colorize one column of the image per exposure. The colors are assigned by mapping the visible color spectrum onto a tiny window around the Si IV 1394 Angstrom emission line. This allows us to see subtle Doppler shifts of the emission line, which are caused by supersonic plasma motions in the solar atmosphere.